Field of the Invention
The present invention relates to an image-forming apparatus, such as a copying machine, a printer, or a facsimile machine, which has a function to form an image on a recording medium such as a sheet material.
Description of the Related Art
FIG. 10 illustrates an image-forming apparatus that uses a typical electrophotographic process. In FIG. 10, sheet materials 1 are stacked in a sheet tray 2. When a host computer, not illustrated, that is connected to the main body A (apparatus main body) of the image-forming apparatus instructs to send a print-job signal, a feed roller 3 disposed in the apparatus main body A rotates, and each sheet material 1 stacked in the sheet tray 2 is fed. The sheet material 1 guided by a conveyance guide 4 is transferred to a transfer unit formed of a nip portion between a photosensitive drum 8 and a transfer roller 9 by using a pair of conveyance rollers 5, and a scanner unit 6 fixes the timing of the transfer with image information formed on the photosensitive drum 8 in a process cartridge B. In the meantime, a toner image is developed on the photosensitive drum 8 by using a development roller 17 in the process cartridge B. Transfer bias is applied to the transfer roller 9 to perform a transfer process, and the toner image formed on a surface of the photosensitive drum 8 is transferred to the sheet material 1. After the transfer process, the sheet material 1 is conveyed to a fixing device 10, and a fixing process is performed by using heat and pressure to fix the toner image to the sheet material 1. After the fixing process, the sheet material 1 is discharged to and loaded on a discharge tray 12 by using a pair of discharge rollers 11.
In recent years, the apparatus main body A is shipped from a factory to a user in a state where the process cartridge B is installed in the apparatus main body A and packed together. The size of packing of the image-forming apparatus is reduced to improve a distribution efficiency.
As illustrated in FIG. 11A, the process cartridge B installed in the apparatus main body A during packing and shipment is secured by using a cushioning material 16 disposed in the apparatus main body A so as not to move due to a vibration or an impact during transportation (Japanese Patent Laid-Open No. 4-350033). The cushioning material 16 is inserted into a space between the process cartridge B and a door 15 in the apparatus main body A to fix the process cartridge B.
However, in the case where the cushioning material16 is disposed in the apparatus main body A, it is necessary for the cushioning material 16 to be removed from the apparatus main body A when the image-forming apparatus is used for the first time in order to prevent malfunction caused by a force applied from the cushioning material 16 to the process cartridge B. More specifically, when the apparatus main body A starts to operate for printing with the cushioning material 16 disposed in the apparatus main body A, a frame body bends due to the force applied to the process cartridge B. This changes a contact pressure between the photosensitive drum 8 and a charge roller or a contact pressure between the photosensitive drum and the development roller 17 in the process cartridge B, and there is a possibility of failures such as a variation in the tint of an image and an uneven image in a direction in which a sheet is fed. Accordingly, as illustrated in FIG. 11B, when a user uses the image-forming apparatus for the first time, the user opens the door 15 in the direction of an arrow Q, extracts the cushioning material 16 in the direction of an arrow R, and removes the cushioning material 16 from the inside of the apparatus main body A.
However, in the case where the cushioning material 16 is disposed in the apparatus main body A, the cushioning material 16 needs to be removed, reducing usability. There is still a possibility that the image-forming apparatus is powered on before the cushioning material 16 is removed, and a force is applied from the cushioning material 16 to the process cartridge B, so that malfunction occurs.